<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #parent {
            background-color: antiquewhite;
        }
        
        .son {
            float: left;
            width: 50%;
            background-color: red;
        }
        
        .son img {
            width: 100%;
        }
    </style>
</head>

<body>
    <div id="parent">
        <div class="son">
            <img src="img/pic01.jpg" alt="">
        </div>
        <div class="son">
            <img src="img/pic02.jpg" alt="" sizes="" srcset="">
        </div>

    </div>
</body>

</html>